Optical navigation systems detect relative movements between the optical navigation systems and target or navigation surfaces to perform tracking operations. An optical navigation system uses a light source, such as a light-emitting diode or a laser diode, to provide illumination light on a navigation surface and an image sensor to successively capture frames of image data in response to the illumination light reflected off the navigation surface, which may be specularly reflected light or scattered light. The optical navigation system compares the successive frames of image data and estimates the relative displacements or movements between the optical navigation system and the navigation surface based on the comparison between the current frame of image data and a previous frame of image data. The optical navigation system is able to track the relative movements between the optical navigation system and the navigation surface by continuously capturing and comparing frames of image data.
Optical navigation systems are commonly used in optical computer mice to track the lateral movements of the mice relative to the navigation surfaces on which the mice are manually manipulated. In a typical optical computer mouse, an illumination lens is used to focus and/or collimate the light from the light source onto a navigation surface and an imaging lens is used to focus light reflected from the navigation surface onto the image sensor. The illumination lens and the imaging lens may be implemented as a single optical component. Conventional optical components used in optical computer mice limit the size reduction of the optical navigation systems, which may be preferred in certain applications.
Thus, there is a need for a system and method for performing optical navigation that uses a more compact optical element to reduce the overall size of the system.